Strategically Designed Uniform MOF‐Derived Nanoporous Carbon Aerogel for Efficient Solar‐Driven Desalination by Control of Hydrophilicity and Thermal Conductivity

Desalination techniques using the photothermal effect hold significant potential for producing fresh water from saline or polluted sources due to their low energy consumption. In the case of commercialized carbon materials are related to heat loss resulting from high thermal conductivity, and metal particles still have trouble in commercialization or cost-effectiveness. This is because a photothermal desalination evaporator must simultaneously exhibit high water evaporation performance, excellent energy conversion efficiency, sufficient hydrophilicity, and low heat loss. In this work, developing an efficient in situ energy utilization technology that instant light to heat energy conversion system based on ZIF-8/agarose-derived carbon aerogels, achieved by controlling hydrophilicity, thermal conductivity, and light absorption properties is reported. The carbon aerogel demonstrates excellent performances of improved capillary force, structural stability, and cost-effectiveness. The designed carbon aerogel, with a high surface area (524 m² g^-1), adequate hydrophilicity, and low density (0.07 g cm^-3), is buoyant enough to float on the water. A water evaporation efficiency of 1.53 kg m^-2 h^-1 under 1 sun and a light-to-heat conversion of 85% are achieved, along with effective salt blocking through the size-controlled uniform ZIF-8 nanoparticles and optimized composition with agarose.